As far as I know there are two ways to toggle fullscreen/get the biggest possible drawing space with a shortcut:

1. Combine Toggle windows display and Toggle layer panel on one shortcut.drawback: If you are in "fullscreen mode" and save, everything except of the timeline toggles back on and your fullscreen mode "gets out of sync". So the next time you press it, the timeline gets visible, but the other windows toggle off.

2. Arrange a Workspace to have no windows and use a shortcut to toggle between the one with windows and the one without. (ONLY PRO)drawback: the viewport and especially the zoom level is different between two spaces. So you always have to adjust your viewport, when switching between the spaces.

How about a shortcut, which allows to hide everything, except the drawing space, while keeping the viewport?

Same here, It's always a system D with multiple shortcuts or using rooms which has some other drawbacks. A simple shortcut to toggle everything except canvas would be a must

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As I'm highly interested in animation workflows, I'm open to scripting new TVP functions for individuals and studios. Please don't hesitate to contact me!

I know there is a ton of stuff on the feature list, but to me it SEEMS like a feature with could be easily added (maybe i'm wrong). Currently I'm using a shortcut which toggles all windows and hides the timeline, but as mentioned above if you save in this kind of fullscreen mode the windows reappear, which forces you to activate the timeline too, to get everything back in sync, which is kinda annoying.